Layers are like transparencies laid over a picture--they allow you
to do a variety of procedures in a file, without changing the underlying
image. For example, you can draw on a layer without obscuring the image
data, you can make "electronic repairs," you can even correct
for color or contrast without changing the original data.

Turn on the Layers pallette in the Window menu.

Window Menu

Once the layers pallette is open, click on the right arrow and select "New Layer." Give the layer
a name and click on "OK." All other settings in this window
should follow the sample below.

Layer menu

Naming layer

All procedures that change the image should now take place with the
new layer selected. You can draw all your letters on one drawing layer,
or
you
can add a
layer
for each letter. You can add additional images to the file, e.g., images
that represent a different light angle, do electronic repairs, all without
affecting the original layer. Layers do, however, increase the size of
the file, so make sure you have enough
memory to
accommodate
large
files.